Map data of road maps and the like used in navigation systems are provided in a recording medium such as a CD ROM, a DVD-ROM or the like in the related art. In addition, map data are provided through communication to a navigation system installed in a vehicle.
However, a system that updates with a high degree of efficiency part of the map data with a large volume provided in a recording medium or the like and allows new and old map data to be used efficiently and with consistency is not provided in the related art.